Solderless waveguide coupling



Nov. 30, 1965 GROSS 3,221,279

SOLDERLESS WAVEGUIDE COUPLING Filed Jan. 21, 1965 2 Sheets-Sheet 1 us I35) l3 l5 INVENTOH'. Irving M.Gross y 5 MM ATTORNEYS.

Nov. 30, 1965 1. M. GROSS ,2 9

SOLDERLESS WAVEGUIDE COUPLING Filed Jan. 21, 1966 2 Sheets-Sheet 2 FIG.4

/NVEN7'0/?. Irving M.Gross ATTORNEYS.

United States Patent 3,221,279 SOLDERLESS WAVEGUIDE COUPLING Irving M. Gross, New Rochelle, N.Y., aSSignor to Portchester Instrument Corporation (a subsidiary of Premier Microwave Corporation), Port Chester, N.Y., a corporation of New York Filed Jan. 21, 1965, Ser. No. 426,788 3 Claims. (Cl. 333-98) This invention relates to a solderless waveguide coupling.

This application is a continuation-in-part of US. application Serial No. 193,549 filed May 9, 1962, now abandoned.

Among the objects of the invention is to provide fluid tight coupling means for waveguides which are highly resistant to pressure and energy leakage and which can be readily applied in the field without solder and with simple tools. The coupling of the invention is employed for attaching other waveguide components to the plane end after cutting a waveguide tube to the length desired at the site of the installation.

Among other objects of the invention is to provide a coupling that can be readily employed to connect to a waveguide section that must pass through a wall, roof, or similar obstruction. In this use, a small opening is cut in the wall or barrier through which a section of the waveguide is passed and the device of the invention is attached to the end of the waveguide section which extends through the Wall.

The objects of the invention are attained by providing (a) a loose flange with one or more set screws by which the flange may be secured to a section of a waveguide, (b) an O-ring, and (c) a large body portion comprising means for attaching the same to the loose flange. The loose flange and then the O-ring are slipped over the cut off end of the waveguide, then the body portion is applied to the end. Thereafter, the waveguide is properly positioned with respect to the body portions of the coupling, by holding the assembly against a flat surface, for example, then the loose flange is secured to body portion and to the waveguide while held in the said desired position.

The construction includes choke structures and provides a coupling with no detectable RF leakage and with a VSWR of less than 1.03. The O-ring is very satisfactory when made of silicone rubber as such a ring will maintain its ductility down to 75 F. and still remain pressure tight. Since waveguide equipment is frequently at least partly installed out of doors, it is necessary to keep the interior thereof air tight to exclude rain, moisture and corroding gases which degrade the properties of the waveguide.

For a better understanding of the nature, scope and characteristic features of the present invention, reference may now be had to the following description and accompanying drawings in which,

FIG. 1 is a side view of the unassembled parts of the coupling of the invention partly held on a waveguide section and ready for assembling thereon.

FIG. 2 is a view similar to FIG. 1 but illustrating a subsequent step in the assembling process.

FIG. 3 is a view of an assembled coupling.

FIG. 4 is a vertical cross sectional view of the joint taken parallel to the axis with the parts separated slightly from the final assembled position.

FIG. 4A is a horizontal, cross sectional, perspective view of the incompletely assembled coupling taken parallel to the axis.

FIG. 4B is a cross sectional view taken on line BB of FIG. 4.

FIG. 5 is a view of a modified form of coupling in the unassembled state.

FIG. 6 is a view of of the device of FIG. 5 after as- 3,221,279 Patented Nov. 30, 1965 sembling but partly broken away to show internal structure.

FIG. 7 is a top cross sectional view of the device of FIG. 6.

The coupling of the invention comprises the loose flange 10, the O-ring 15 and the body portion 20. The loose flange 10 is of a size to fit easily but snugly over a waveguide 30 to which the coupling is to be attached. The loose flange 30 comprises a plurality of threaded, set screw holes 11 extending inwardly from the rim to the interior opening of the flange and a plurality of openings 12 extending longitudinally through the sides of the flange. Openings 12 may be threaded or not but are preferably unthreaded. Set screws 13 (FIG. 4B) are provided to fix the loose flange 10 on the waveguide 30. Attaching screws 14 are also provided for attaching the loose flange to the body section 20.

As indicated above, the O-ring 15 is preferably made of silicone rubber. The loose flange 10 has an interior bevel 17 and the adjacent end of body section 20 also contains a similar interior bevel 18 (see FIG. 4) to position and compress the O-ring 15.

The body section 20 comprises a portion 22 of approximately the same cross sectional shape as the flange 10. Thus, portion 22 has an interior opening 23 adapted to receive the end of the waveguide 30. At least two sides 24, 25 (see FIG. 4A) of the portion 22 extend outwardly from the opening 23 a suflicient distance to contain threaded openings 26 (only one shows in FIG. 4) for attaching the loose flange 10 thereto. The other two sides 27, 28 of the portion 22 (see FIG. 4) may be narrower than those sides 24, 25 which provide for attaching the loose flange 10. The body portion 20 may also contain suitable means such as the enlarged flange 29 for attaching to other parts of the waveguide apparatus. Suitable attaching means such as the openings 31 may be provided in the enlarged flange 29.

As shown in FIG. 4A the L-shaped choke cavities 35, 36 are formed in the two opposite wide sides of the opening 23. The lengths ADB and ADC of the assembled device presents an electrically equivalent short circuit at points B and C and an electrical equivalent open circuit at point D. Without the choke, microwave energy would tend to leak at ends B and C. The addition of the choke sets up a low impedance path at point B which prevents energy leakage.

The enlarged flange 29 of FIGS. 1-4 can be replaced by a second loose flange and a second O-ring as illustrated in FIGS. 5 and 6. In this form of the invention the body portion 120 contains tapped openings 126 extending into both ends thereof so that loose flanges 10 and may be attached at both ends of said body portion 126 with the sealing O-rings 15 and therebetween. In this way, the waveguide section 30 is sealed to the waveguide section 130.

In the device shown in FIGS. 5-7, the waveguides 30 and are similar in size and similarly positioned, however, the device of FIGS. 5 and 6 can be designed to unite waveguides of different dimensions or waveguides which are differently oriented with respect to the minor and major dimensions thereof. In order to provide for proper positioning of the two ends of guides 30 and 130 respectively, the internal flange or ridge 116 is provided in the body portion 120. The height of the flange 116 is equal to the thickness of the guides so that a smooth internal fit is provided.

The features and principles underlying the invention described above in connection with specific exemplifications will suggest to those skilled in the art many other modifications thereof. It is accordingly desired that the appended claims shall not be limited to any specific feature or details thereof.

I claim:

1. A solderless coupling for a waveguide comprising a loose flange having an interior opening adapted to fit snugly about a waveguide,

a body portion having a rectangular interior opening adapted to fit snugly about a waveguide,

an O-ring adapted to fit about said waveguide;

said loose flange having a plurality of openings in at least two sides thereof extending in the direction of said body portion, t

said body portion comprising a plurality of openings matching said openings of the loose flange whereby the loose flange may be secured to the body portion with the O-ring therebe'tween,

said loose flange containing a second series of openings extending inwardly from the rim to the interior opening thereof, 7

said second series of openings in said loose flange being tapped so that the latter can be fixed to the waveguide,

said body portion having :a pair of choke openings extending from the inner surface of the wide sides of therectangula'r opening toward the outerside thereof.

2. The solderless coupling as claimed in claim 1 wherein the body portion comprises a set of openings at each end thereof,

a second loose flange and a second O-ring whereby said coupling is adapted to unite the ends of two waveguides.-

3. The solderless coupling as claimed in claim 2, whereing said body portion comprises a centrally located internal flange adaptedto contact the ends of the two waveguides, the height of said flange being approximately equal to the thickness of the walls of said waveguides.

References Cited by the Examiner UNITED STATES PATENTS 2,170,393 10/1939 Tornblom. 2,329,876 9/1943 Castellano 2s5 9o 2,459,201 1/1948 Thoin'a's 333--96 HERMAN KARL SAALBACHQPfiinary Exdmihr. 

1. A SOLDERLESS COUPLING FOR A WAVEGUIDE COMPRISING A LOOSE FLANGE HAVING A INTERIOR OPENING ADAPTED TO FIT PORTION HAVING A RECTANGULAR INTERIOR OPENING A BODY PORTION HAVING A RECTANGULAR INTERIOR OPENING ADAPTED TO FIT SNUGLY ABOUT A WAVEGUIDE, AN O-RING ADAPTED TO FIT ABOUT SAID WAVEGUIDE, SAID LOOSE FLANGE HAVING A PLURALITY OF OPENINGS IN AT LEAST TWO SIDES THEREOF EXTENDING IN THE DIRECTION OF SAID PORTION, SAID BODY PORTION COMPRISING A PLURALITY OF OPENINGS MATCHING SAID OPENINGS OF THE LOOSE FLOANG WHEREBY THE LOOSE FLANGE MAY BE SECURED TO THE BODY PORTION WITH THE O-RING THEREBETWEEN, SAID LOOSE FLANGE CONTAINING A SECOND SERIES OF OPENINGS 